The overall performance of a detergent product for use in washing or cleaning method such as laundry, dishwashing, household cleaning, is judged by a number of factors, including the ability to remove body soils, greasy/oily soils and the ability to prevent redeposition of the soils or the breakdown products of the soils on the articles in the wash.
The complex nature of everyday "body" soils typically found on pillow cases, T-shirts, collars and socks, provides a thorough cleaning challenge for detergents. These soils are difficult to remove completely and often residues build up on fabric leading to dinginess and yellowing. Greasy/oily soils and stains represent also a well-known cleaning challenge often met by the inclusion of a lipolytic enzyme in the detergent compositions.
It is therefore an object of the present invention to provide detergent compositions, including laundry, dishwashing and household cleaning compositions, which provide cleaning performance on body soils and/or oily/greasy soils and stains.
The above objective has been met by formulating detergent compositions comprising an enzyme that increases the water-solubility of saturated fatty acid-containing stains/soils. These enzymes enhance the removal of such stains/soils by directly reacting with the saturated fatty acid components of the stains thereby increasing the water-solubility of said fatty acid component and resulting in an overall increase in stains/soils removal.
It has been further found that the overall performance of the detergent compositions of the present invention is optimised by the addition of another detergent enzyme, especially a lipolytic enzyme and/or a polymeric soil release agent.
According to the present invention, prefered enzymes that increase the water-solubility of saturated fatty acid-containing stains/soils are e.g. the acid-thiol ligase, desaturase and gluthathione S-transferase enzymes.
Acid-thiol ligases are commonly used in the determination of free fatty acids and of lipase activity (JP1020099; EP 273 647; U.S. Pat. No. 4,491,631; JP56158097; U.S. Pat. No. 4,360,591; JP60233560) and in pharmaceuticals products (U.S. Pat. No. 4,822,776). Desaturase enzymes are mainly described in transgenic plant production such as in the most recent WO96/21022, WO96/13591, U.S. Pat. No. 5,430,134, WO95/18222, WO94/18337, EP 644 263 as well as for the production of seed oil containing altered levels of saturated--unsaturated fatty acids such as in the most recent U.S. Pat. No. 5,443,974; WO94/10189; EP 561 569; WO91/18985; WO91/13972. The glutathion S-transferase enzyme is used in plant resistance to herbicide (WO97/11189 and DE 19 501 840) or in medical treatment and/or diagnostic such as in the most recent J09 0330521, J09 021 806, RU2 063 044, WO 96/40739, WO96/40205, J08 245 424, WO96/31779, J08 059 501, WO96/02674.
However, the use of an enzyme that increases the water-solubility of saturated fatty acid-containing stains/soils has never been previously suggested in detergent compositions, nor the benefits resulting therefrom when used in detergent compositions, have been recognised.